GSIs range from projects like green roofs and bioswales to rain gardens and rainwater cisterns that absorb stormwater in an attempt to control runoff, the report said. Major cities like New York and Philadelphia have implemented similar infrastructures, which the report said are effective in controlling minor flooding.

Together North Jersey described Newark's combined sewer system as an "outdated and overburdened" one that collects rainwater runoff in the same pipes as domestic sewage and industrial wastewater. When rainfall "exceeds the system's capacity it overflows, carrying diluted human and industrial waste, toxic materials, and debris into streets, basements and waterways," it said.

In addition to other initiatives the city is taking to combat the issue, the plan recommended ten GSI projects to consider on city-owned land in three Newark neighborhoods:

East Ferry Neighborhood

The study suggests a stormwater planter, landscape plantings, and pervious concrete sidewalk on Horatio Street. The estimated cost of the GSIs would be between $198 and $253,000, it said.

Stormwater planters on Christie Street would cost between $84 and $102,000, it said.

Planters, pervious concrete sidewalks, and curb reconstruction would make a difference at the intersection of Market and Read Streets, the study said. They'd cost between $301 and $366,000.

The study recommended rain gardens be added to the areas near Riverfront Park for a cost of $18 to $45,000.

Fairmount Neighborhood

For a vacant lot at 12th and Fairmont Avenues, the study suggests clearing, rain gardens, adding plantings and other amenities, stormwater planters, pervious concrete sidewalks, a cistern, a public gathering space, and permeable pavers. Altogether, it could cost up to $216,000.

For a vacant lot on South 8th Street at North Star Academy, suggestions include a pedestrian pathway and retaining and seat wall. Those and other GSIs at the spot could run up to $109,000, it said.

It suggested street tree planters and pervious concrete at the Sussex Avenue School site, for $58 to $72,000.

Lower Broadway Neighborhood

At the Broad and Clark Community Garden, suggestions included a permeable paver entrance and stormwater planter. All of the recommendations at the spot could run up to $146,000.

The study suggested adding rain barrels and downspout planter boxes to Mount Pleasant Avenue for up to $77,000.

For between $196 and $239,999, the city could add stormwater planters, pervious concrete sidewalks, and reconstruct the curbs on Dr. Martin Luther King Boulevard, it said.

The study acknowledged that the city would need new sources of funding and increased personnel to carry out the GSI initiatives. It suggested several sources for the funding, including agreements with developers, and statewide legislative changes that would include GSI funding for New Jersey cities.

Still, Newark Mayor Ras Baraka issued statements in support of the study and its suggestions.

"We are proud to have partnered with Together North Jersey to develop the Newark Greenstreets Initiative to create innovative solutions to these issues," Baraka said in the statement.

"These will enable us to transform Newark into a safer and healthier city."